There is a cable adjustment note in Bentley but personally,
I've never fully understood it. I adjust the cable so i can feel a
little slack. Like light finger pressure pushes portion of cable
near throttle over only ~ 3/8" or 1/2".

I've often wondered if broken motor mounts can cause
the issue you're seeing.

Years ago, I road around in my '58 Beetle with a failing
mount at transaxle nose. The movement in the drivetrain
would pull on the clutch cable and most likely, the
accelerator cable. I would have to jerk the drivetrain
by popping the clutch to get idle back to normal
and not have a slipping clutch.

Were it me, if I could replicate the issue then pull over
as you say, I'd have a pry bar handy and CAREFULLY
pry drivetrain forward and see if that drops the idle.
OR, I'd make marks between frame and engine
when idle is ok, and marks when idle is high.

Neil.

On 6/24/15, Steve Williams <steve@williamsitconsulting.com> wrote:

> I have a 91 Westfalia, manual.
>
> After driving for a short period of time, when I take my foot off the
> gas, the engine only idles down to about 1800 rpm.
>
> If I "burp" the throttle... by pressing gas pedal towards the floor &
> releasing quickly, the idle will come down to normal.

> Annoyingly, I can't replicate this without driving the vehicle. Humm...
> as I'm typing this email, I just thought of driving the vehicle, pulling
> over to the side of the road & popping the back open...  but until I get
> a chance to do that, is there any "list wisdom" that could give me
> pointers on where to look?
>
> Additionally, how tight should the throttle cable be?  There is about
> 1/2 inch of slack in the throttle cable.  It is not very clear if it's
> adjustable on the engine end of the cable or not...

--
Neil n

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